Multiple safety valve interlock



March 13, 1956 R. A. sHu-:LDS 2,737,971

MULTIPLE SAFETY VALVE INTERLOCK L |===1l Z INVENTOR WMM March 13, 1956 M, SHlELDs 2,737,971

MULTIPLE SAFETY VALVE INTERLGCK Filed DSC. l2, 1950 3 SheetS-Sheet 2 INVENTQR March 13, 1956 R. A. sHn-:Lns 2,737,971

MULTIPLE SAFETY VALVE INTERLOCK 3 Sheets-Sheet 3 Filed Dec. l2, 1950 A, l ELE-5 E INVENTOR @www United States Patenti() SAFETY, VALVE INTERLQCK Robert A Shieldsgl` Bloomsburg, Ba.; assigner to American Car andiFoundry,Company;.New;Ynrk,iN. Y.,a conof New: Jersey y i Application December lf2, 1950, Serial No; 200,333

8- Claims.:A (Girly-422) 1 This '.,invcnticntclatcsic Safety valves in general. and

in particulartc multiple. YSafctyvaivcs fQr usc .with Linfiamniiiiccr ccrrcsivcgccs in Sfcragc cr transitandi is a ccntinuatlcnin Part cf my application. Serial-Nc- 732,979;.1cdMarch 7, 194.7'I v110W ..,Patcnt.2;53,8;3`3`5; granted January 1'6, 195 1 In thcstcragc. ci highly inii'cmmablccr ccrrcsivcgascs ndlifqnidsiflis necessarythtthclccntaincrs bc provided Withfsnfciyylvcs, ,cach cr @combinationfhcrccfibcing cf snfiicicnf-fcapacitylns tc fnllyprctcctethccontainer, Undcrlprcccntlsystemfs cnc ,-cr mcrcsafcty vaivcsmay bc removed..cithcrintcnticnally 4cr vaccidcntally. leaving thesfcragctnnkrwithcnt adequate prctccticn andl ,Since Provision is made. fcr rcmcval .under .Pressure ithcrc is opportunityvQ-for deliberate (sabotage with ,discharge lof thegcontents of thecontainenBy providing a plurality 0f Safety valvcsgcnl'y Qnccff which canfbc removed. itis Theseand:,othenobjeetsbf the,invention\ will, be ap- Y parent to persons v,skilled the art .from a lstuqlvifof the fclicvving i Y icscripticn. and 7 accompanying drcvvingsmin Whichf.; i

- thelccnfraincrand tvccf, thc Scfctyfvalvcs;

` Fig .2 is sectional-view taken substantiallypn line 212-0t Figa .L with certain-Parts brclccn-iV awaytc better dicclcsc-thcconstructionl Figfiw `ic a-lsccticnaiiyicw taken: substantially cn 4line 3-7- 3 of FisiciV and. 4.Showing in dcteil the :interlock cy1- mdc ing the tr'narlrierLiIl whichsfoursafety fvalve assemblies are interconnected; i

` is af diagrammatic epiping Y arrangcnicntf. show.-

Fig.;l 5 isgassectionalllview of asIightIy-mOdied form of safetyA valve assemblyfand showing the safety .,valve readygto be removed@` Figig6- isga :sectional lview of the-valve. of Fig. 5v but showingA `the parts infully seated and locked position, and

Fig. 7` is a` diagrammaticview of yafpiping varrangement f for gconnecting- ,af plurality Vof safety valve if assemblies such as shown/in ligs.V Stand 6.. i

Referring nowto. the drawings in detail `it .will be seen that .the :container ,walls 4.haverwelded therein tubessor sleeves 16 finished internallyiat .the lower endE asatS `and at thenlpper endlas at 10. iThelower iinishedsurface 8 is adaptedto be engagedgby a.resilientspackingring` 12 carried by a stop valveilst.` `This stop-valveis provided withf'agmetalliejseat; -16 adapted tolengage-aA corresponding 2,737,971 Patented Mar. 113 9.755

is gvidcdby rctaining bolts 18 and ccnstanty nrgcdgtcward' aseatedsposition on tube 6 by springs 20. The upperiinishedsurface 10 of the tube or sleeve isadapicd to engagea resilient packing ring 22` carried by vsafety valve body24 clamped in position by means of bolts26 andajring 28 Vinto which, is fastened an exhaust stackq. The bolts 2 6 are engaged in acollar ,32' welded'or Votherwise` securedto theupper or outer end ofthe tube o r sleeye, 6. 'Ihe safety valve body has attached theretoa tubularextension 34 fitting Vwithin the slee ve ,6] and` tQ this tube ijs welded or otherwise rsecured alocking vring 35 which is adapted to engage a s1eeve36 'weldedor otherwisesecured to Vthe upper surface Vof stop valve14. The `lower ,edge of this sleeve 36 is provided with openings7 throughwhich gasesmay escape and :pass: upwardlynto the safetyfvalve. The safety valve, itselis held on itsseatby means of, a spring 578 actingon the valve gbody 2 4 and a washer 4 0 carried. by the valve'stem 42. Sealing ,between .the safetyvalveand bodyis aecomplishzedby means of ametallie seat and resilient seal arrangement 44 more `fully described. in application 720,0,7 2 rii led January 1947,-,now Patent 2,599,622, granted June 10,u 19152. i

Whengit is desired to remove a safety .valve,f.and `neg lectigng`, f or :the `time .being :any reference to. the interlock,-

img cylinders, itwilltbe .seen-that when the safety valve assemblyv on ,ltherightlrsideof Eig.l moves upwardly, duetoiunscrewing .the nuts .on bolts, 26, thegpressurewithin the,slee ve @will `causethe assembly to move upwardly in thcsiccvcf-.With leakage. prevented 4by thc Scaling ring 22d Whcnl, ltcvvcvcn'thc asscnibly has shificd. upwardly a Snfiicicntzdistanccfthc1stop yaivc 14, whicnhasbccn followingfthe safety yalveassembly upward under pres,- surepf spring-120, willhavebecome seated and; following its scntingandscalingthcresilientring 22 will pass above ventsft and permit escape of pressure trappedvbetween the safetyyalveseat andthe stop valve seat-.After this pressure has v escape through vent; 46 the entire-- safety valve assembly -gmayq-be comp lete 1yremoved` from4 the sleeve 6 with the pressure retained in the container by the stop valve ;j14 throughs its metallic seat 16 and resilicnt. seal 12- f i In order ,to interlockthe safety valves andprevent removal :of more than-one; safetyivalve, lock cylinders L are l:wedded or otherwise secured toiy the tubes or sleeves. TheseY locking cylindersas clearly shown, have; their inner Vends projecting through an opening in the sleeve .6 andthe interior surface is finished to provide an enlarged bore 48 and lavzreduced bore 50. A piston and rod as-V sembly havingtan enlarged piston portion 52 and a long rod .portiona54 `and short rod portion 56 is-mounted the locklcylinder.: The piston: portion 52 g is grooved to receivearesilient packing member 58, lwhile the short rodiportion56 isrgrooved to. receive a resilient sealimember .60. The long vpiston rod portion 54 :is grooved -to receive afresilient sealingring 62 adapted-to engage and seal with a filler member 64 welded or other wise -secured in the vopen end of the lock cylinder-L. Outwardlyof the sealing ring 62 the rod 54 isprovided with a-locking end portion-66 adapted to project over the locking -ring 35 ofVr the safety valve assembly; Sealing rings 60 and 6 2 and accordingly the ends of therods S4 and56 are of the same cross-sectional area so as to give a1 balanced valvejarrangemenh It isfto be noted that the rods `54V and v5 6 have a hole 70 bored therethrough which permitsinterhange yof pressure between the ends of the pistonrods, The chamber'between packingrring 5 8 and the head of the lock ,cylinder is connected tothe interior .cf thc-:pressure ccntaincr ,4 rby means .ci a smallpassage 7 2,w.hi1c.;,thc chamber, te the .cppcsitesidc .nt the sealing ring 58 is vented to the exterior of the lock cylinder through a nipple connection 74.

As clearly shown in Figs. 1 and 4 each nipple 74 of each lock cylinder L is connected by piping P to the interior of each tube 6 other than the tube to which the lock cylinder is connected through a check valve assembly C, having the valve 76 thereof opening in a direction permitting tiow of material under pressure into the interior of the associated tube 6 but preventing tlow of `material out of the tube through the piping. Certain of .the check valves will be provided with a leakage passage 77 or a controlled by-pass. In any case the rate of leak age will be predetermined so as to control the time interval for release of the locks after reinsertion of a removed safety valve assembly. Connections to the various tubes will be made through the use of Ts 78 or similar piping connections as clearly shown in Fig. l. Referring specifically to Fig. 4 it will be seen that the ycircles designated 1, 2, 3 and 4 represent the entire valve assemblies and specifically the large tube 6 of the assembly and which can be closed either by the safety valve, as shown at the right in Fig. 1 and in which case V,the entire tube is subject to container pressure, or the bottom may be closed as shown at the left of Fig. 1, in which case the interior of the tube is subject to atmospheric pressure. The small rectangles representing the locking cylinders are designated L1, L2, La and L4 corresponding respectively to the tube of the assemblies to which they are welded. Likewise, the various check valves C, which are connected in the lines to the respective locking cylinder, are given the same subscript as the locking cylinder to which they are connected. Thus it will be seen that the pipe extending from locking cylinder L1 to assemblies 2, 3 and 4 has'a check valve C1 interposed in the pipe line adjacent each tube and controlling the ilow of matter under pressure out of assemblies 2, 3 and 4 to the lock cylinder L1. As previously stated certain of the check valves have a leakage passage therein, for example, check valves C2, C3, C4 connected to assembly 1 and check valve C1 connected to assembly 2. In other words one check valve in each line will be provided with a small leakage passage for the purpose of charging the pipe lines with pressure after return of a removed valve.

Assuming that check valve assembly 1 has been removed to the position shown in the left of Fig. l, then the stop valve 14 will have closed and the interior of tube 6 will be at atmospheric pressure. The check valves C2, C3 and C4 located adjacent assembly 1 will permit ow of material out of the pipe lines to which they are connected. Venting of material through check valve Cz of assembly 1 will vent the chamber inclosed between sealing rings 58 and 62 of locking cylinder Lz, immediately causing the piston to move placing the locking end 66 above the locking ring 35 as clearly shown in the right hand of Fig. l. Venting of material through the check valves C3 and C4 immediately adjacent assembly 1 will likewise cause immediate locking of the lock assemblies L3 and L4 respectively. Escape of material under pressure from assemblies 2, 3 and 4 into the pipe lines P is prevented by the check valves such as Ca and C4 immediately adjacent assembly 2, also by C2 and C4 immediately adjacent assembly 3 and by C2 and C3 immediately adjacent assembly 4. Locking cylinder L1 does not move since the pipe line connected thereto is not venting, since assemblies 2, 3 and 4 are in position and locked in the closed position as shown in the right of Fig. l. Thus it will be seen that removal of any one of the safety valve assemblies causes a venting of all pipe lines connected to the tube 6 from which the assembly is being removed and will cause all locking cylinders to move immediately to locked position, excepting that locking cylinder which is welded or otherwisesecured to the tube 6 from which the safety valve assembly is being removed. It will also be seen that ow of material into the pipe 4 lines is either prevented or under predetermined control by the various check valves C connected adjacent the tubes 6 of assemblies which are in position and under pressure.

Insertion of the removed saftey valve assembly will bring the locking ring 35 into engagement with the stop sleeve 36 and upon pressure being applied through the nuts of bolts 26, the safety valve will be forced downwardly unseating stop valve 14 and again subjecting the interior of the tube 6 to pressure. Prior to this time, however, the sealing ring 22 and safety valve will have closed the upper end of tube 6, thus permitting immediate build up of pressure within the tube 6 as soon as the stop valve 14 has been unseatcd sutiiciently to allow entrance of pressure. As soon as the pressure builds up in a tube into which an assembly such as 1 is being inserted, material will flow through leakage passage 77 in certain of the check valve assemblies and at a predetermined rate. As soon as the pressure has built up within the pipes to substantially container pressure, thenthe balanced condition of the locking cylinders will be reestablished and springs 80 will cause movement of the locking cylinder pistons to a retracted position 'such as shown in the left hand portion of Fig. 1.

From the preceding it will be seen that removal of any assembly causes immediate locking of all other assemblies and by means which is not under control of the person removing the assembly. The locking cylinder associated with the assembly being removed will not lock and accordingly can not hamper reinsertion of the assembly after necessary inspection and repair. When the assembly is again reinserted in itsl associated tube there will be a short interval of time before pressure will have built up in the previously vented pipe lines sutlciently to unlock the remaining assemblies. The time interval can be controlled through proper choice of the leakage passage or by-pass associated with certain of the check valves as pointed out. It is obvious that all of the check valves need not be provided with leakage passages, but that only one check valve in each pipe line need be provided with either a leakage or controlled passage.

In the form shown in Figs. 5, 6 and 7 a slight modication has been made in order to simplify the piping arrangement within the container and wherever possible the same reference numerals have beenv applied as have been used in connection with Figs. 1 to 4 inclusive. In this form the sleeve 36 fastened to stop valve assembly 14 has quite close clearances with the interior walls of the associated tube 6. In this form when the safety valve assembly has been removed sufficiently to vent tube 6, as shown in Fig. 5, the locking end 66 Will strike against the upper end of sleeve 36 thus preventing the locking end projecting into the tube a suflcient distance as to prevent the reentry of the safety valve into-tube 6. In other words, the locking end 66 can not block the passage of locking ring 35, nor prevent this ring contacting the upper end of sleeve 36 in order that the assembly may force the stop valve oi of its seat. Since the locking cylinder can not block reinsertion of the -safety valve assembly, the piping can be much simplied as clearly shown in Fig. 7. In this simplified arrangement each valve assembly 1, 2, 3 and 4 requires in addi tion to its associated locking cylinder L1, L2, L3 and L4 only one check valve, namely, C1, C2, Ca and C4. 'I'hese check valves are constructed similar to those previously described in that they normally prevent, or at least control, the ow of pressure out of the tube 6 into the pipe lines connecting the various assemblies and locking cylinders. At least two of the check valves will be provided with predetermined leakage passages 77 so that the pipe line can be recharged upon reinsertion of a safety valve assembly which has been removed. v y

It will be obvious that with this arrangement removal of a safety valve will cause all locking cylinders to move toward lockedtposition, but the locking cylinderassociated with the tube from which the safety'val've isb 'eiug re moved can not move completely to alocltedpositi'on^ since it is blocked by the extended sleeve 3 6 of'thegstop valve I4. Reinsertion of the'removed'safetyvalvewillbe'pos sible due to the blockingof the associated'locking cylinder andv whenpressure is reestablishedin tube 6, thenpressure can build up in the pipeline andvpermit .moving of all locking cylinders to the unlockedposition.

With the formasshown in Fig. 7H addition ofa safety valve assembly requires only the addition of' the safety valve with its associated loclclingcylindep and check valve C." `Withthefforrn such as showninFig; 4 additionof a safety valvef assembly will, of courseirequire not'y only: addition of the safety valve assembly audits-associated;locking cylinder'L, but willalso requirethe addition@ of'fcheck valvcsn aquantityY equalingone-lessthan the total numben of; safety valves inA use multiplied" times; two'.v In other words, the totalf number of check valves; required willlbe` the total number of safetyy valve assemblies;-4 involvedi minus onev times the totalnumber of the, safety valve assemblies. Itis accordingly-obvious thatf'on large groupings of valves the system shown in Fig. 7 is much more preferable.

What is claimed is:

1. A multiple valve system for pressure containers comprising, more than two tubes projecting into and Secured to the container, a safety valve assembly closing the outer end of each of said tubes, a projection extending inwardly from each safety valve assembly, a vlocking ring secured to each of said projections, a stop valve secured to the inner end of each of said tubes, a sleeve secured to each stop valve and extending upwardly into the associated tube into engagement with said locking ring whereby said stop valve is normally held open by said safety valve projection but is adapted to close the inner end of the associated tube upon removal of the safety valve, lock means carried by each tube and all but one thereof being movable by pressure within the container into a position above the associated locking ring upon removal of any one safety valve to thereby prevent removal of but one safety valve at a time when said container is under pressure, piping connecting the locking means of each tube to the remaining tubes, and a plurality of check valves in said piping controlling ilow of fluid under pressure from the tubes to said locking means.

2. A multiple valve system for pressure containers comprising, more than two tubes projecting into and secured to the container, a safety valve assembly closing the outer end of each of said tubes, a projection extending inwardly from each safety valve assembly, a locking ring secured to each of said projections, a stop valve secured to the inner end of each of said tubes, a sleeve secured to each stop valve and extending upwardly into the associated tube into engagement with said locking ring whereby said stop valve is normally held open by said safety valve projection but is adapted to close the -inner end of the associated tube upon removal of the safety valve, lock means carried by each tube and movable by pressure within the container into a position above the locking ring to thereby prevent removal of but-one safety valve when said container is under pressure, piping connecting the locking means together and to each tube, and a plurality of check valves each located in the piping adjacent a tube and controlling the ow of fluid under pressure from the tubes to said locking means.

3. A multiple valve system for pressure containers comprising, more than two tubes projecting into and secured to the container, a safety valve assembly closing the outer end of each of said tubes, a projection extending inwardly from each safety valve assembly, a locking ring secured toeach of said projections, a stop valve secured to the inner end of each of said tubes, a sleeve secured to each stop valve and extending upwardly into the associated tube into engagement with said locking ring whereby saidi stop;A valve` is-I normally hel'd openv byV said' safetyv valveY projectionbut isl adapted*VV toclose the'A inner end of the associated tubet upon removal' of the safety valve; lock meansr carried/byr eaclii-tubeandmovable by pressure wit-hin the container into a' position `above the locking ring to thereby=prevent removal5 of but-tone safety valvewhen; said containerisunder pressure, piping coni' necting the locking rneansftogetlier` andtofeachrtube; and aplurality'oficheckvalves each located in the-'piping'v ad'- jacent aftubeandcontrolling the flowlof fluidlunderfpres.- surefrom the tubes to s aid lockingjmeans, certainV of-said check" valves being provided;l withvv leakage' passages' of predetermined area. Y i

Y 4. A multiple valve system forr pressurej containers comprising, more# than' two tubes' projecting intol and securedl to` the, container,V a safetyVv valve assembly closing the outer'end: of each of saldi tubes; a projection-extendi ing inwardly into the associatedtubefrom each safety valve 'assembly and movable. outof' the tube during re:- moya'l of the valve' assembly, a stop valve. securedtto the inner end'of eachV of` saijcl tubes and' normally held open by" thesafety valve projection' butadapted to close the innerN end of the tube upon removal of theI safetyjvalve; lock' cylinders connected to'each otr'aid tubes, a piston in each cylinder and movable into engagement with said projection to control removal movement of the projection and associated valve assembly, a conduit connecting the lock cylinders to each other, other conduits connecting the interior of each tube to said first conduit, and a check valve in each of said other conduits to control flow of iiuid under pressure out of said tubes into said first mentioned conduit.

5. A multiple valve system for pressure containers comprising, more than two tubes projecting into and secured to the container, a safety valve assembly closing the outer end of each of said tubes, a projection extending inwardly into the associated tube from each safety valve assembly and movable out of the tube during removal of the valve assembly, a stop valve secured to the inner end of each of said tubes and normally held open by the safety valve projection but adapted to close the inner end of the tube upon removal of the safety valve, lock cylinders connected to each of said tubes, a piston in each cylinder and movable into engagement with said projection to control removal movement of the projection and associated valve assembly, a conduit connecting the lock cylinders to each other, other conduits connecting the interior of each tube to said first conduit, and a check valve in each of said other conduits to control ow of fluid under pressure out of said tubes into said first mentioned conduit, certain of said check valves being formed with leakage passages of predetermined area.

6. A multiple valve system for pressure containers comprising, more than two tubes projecting into and secured to the container, a safety valve assembly closing the outer end of each of said tubes, a projection extending inwardly from each safety valve assembly, a stop valve secured to the inner end of each of said tubes and normally held open by the safety valve projection but adapted to close the inner end of the tube upon removal of the safety valve, lock cylinders connected to each of said tubes, a plurality of conduits each connecting each of said lock cylinders to the interior of the remaining tubes, and a plurality of check valves in said conduits adjacent each tube, certain of said check valves preventing flow of uid under pressure from the tubes into the conduits and other of said check valves being provided with leakage passages of predetermined area to control the rate of ow of fluid under pressure from the tubes into the conduits.

7. A multiple valve system for pressure containers comprising, more than two tubes projecting into and secured to the container, a safety valve assembly closing the outer end of each of said tubes, a projection extending inwardly from each safety valve assembly, a stop valve secured to the inner end of each of said tubes and normally held open by the safety valve projection but adapted to close the inner end of the tube upon removal of the safety valve, lock cylinders connected to each of said tubes, a plurality of conduits each connecting each of said lock cylinders to the interior of the remaining tubes, and a plurality of check valves in said conduits adjacent each tube and operable to permit free low of material under pressure from the conduits into the tubes and controlled ow at a predetermined rate from the tubes into the conduits.

8. A multiple valve system for pressure containers comprising, more than two tubes projecting into and secured to the container, a safety valve assembly closing the outer end of each of said tubes, a projection extending inwardly into the associated tube from each safety valve assembly and movable out of the tube during removal of the valve assembly, a stop valve secured to the inner end of each of said tubes and normally held open by the safety valve projection but adapted to close the inner end of the tube upon removal of the safety valve, lock cylinders connected to each of said tubes, a piston in each cylinder and movable into engagement with said projection to control removal movement of the projection and-associated valve assembly, a lirst conduit connecting all of the lock 'cylinders together, a plurality of other conduits each connecting the interior of a tube to said lirst conduit, and a one-way check valve in each of said other conduits and operable to permit substantially free ow of matter under pressure into the tube from said lrst conduit, at least two of said check valves being provided with leakage passages providing a predetermined rate of ow from a tube into the rst conduit.

References Cited in the tile of this patent UNITED STATES PATENTS 568,572 Hewson Sept. 29, 1896 596,634 Smith Jan. 4, 1898 668,589 y Snider Feb. 19, 1901 744,625 Sarver Nov. 17, 1903 1,105,061 Carpenter July 28, 1914 1,905,149 Chryst Apr. 25, 1933 1,995,910 Wyeth Mar. 26, 1935 2,258,376 Clothier Oct. 7, 1941 2,463,253 Earle Mar. 1, 1949 2,538,335 Shields Jan. 16, 1951 

